An early evaluation of bleeding-related hospital readmissions among hospitalized patients with nonvalvular atrial fibrillation treated with direct oral anticoagulants

Deitelzweig S, Bruno A, Trocio J, et al.
Curr Med Res Opin 2016;32:573-582

Background

Patients with nonvalvular atrial fibrillation (NVAF) have high hospital readmission rates [1,2]. These rates are based on all-cause AF-related and cardiovascular related readmissions, however little information exists on bleeding-related readmissions specifically. In clinical trials, NVAF patients treated with different direct oral anticoagulants (DOACs) differed in bleeding rates [3-6]. No studies have evaluated the impact on hospital readmissions for bleeding among NVAF patients in relation to the DOACs dabigatran, rivaroxaban and apixaban, as they have only quite recently been launched on the market.

The primary objectives of this study were to perform two real-world database analyses to evaluate the frequency of bleeding-related hospital readmissions among hospitalized NVAF patients treated in the US with dabigatran, rivaroxaban or apixaban. These included 4138 apixaban-, 32,838 dabigatran- and 37,754 rivaroxaban-users. Study populations were derived from the Premier Hospital database and the Cerner Health Facts hospital. These cohorts were analysed separately.

Main results

During hospitalization:

• For both study populations: Patients who received apixaban were significantly older (73.6 years) compared to dabigatran (71.9 years) and rivaroxaban (72.3 years) (P<0.001) and had significantly higher risks of stroke and bleeding based on mean CHADS₂ score (apixaban: 2.19 vs. dabigatran: 2.09 vs. rivaroxaban:2.04, P<0.001) and mean HAS-BLED scores (apixaban: 2.56 vs. dabigatran: 2.33 vs. rivaroxaban: 2.35, P<0.001). Also the mean Charlson Comorbidity Index (CCI) score was significantly higher for apixaban patients (2.35) vs.dabigatran (2.12) and rivaroxaban (2.09) (P<0.001).
• For both study populations: Relatively more apixaban-treated patients suffered from stroke or bleeding, followed by rivaroxaban- and dabigatran-treated patients.
• For both study populations: Relatively more rivaroxaban-treated patients concomitantly received warfarin (9.8%) than those who received apixaban (7.7%) and dabigatran (6.6%) (P<0.001).

Bleeding-related hospital readmissions:

• For the Premier Hospital cohort: Frequency was greatest for rivaroxaban-treated patients, followed by those who received dabigatran and apixaban (1.9%, 1.5%, 1.5% respectively, P<0.001).
• For the Cerner Health Facts hospital cohort: No significant difference between treatments.

All-cause hospital readmissions:

• For the Premier Hospital cohort: Frequency was greatest for rivaroxaban-treated patients, followed by those who received apixaban and dabigatran (15.4%, 14.4%, 13.8% respectively, P<0.001).
• For the Cerner Health Facts Hospital cohort: No significant difference between treatments.

Bleeding-related hospital readmission odds after adjustment for key patient characteristic:

• For the Premier Hospital cohort: Were 1.4-fold (P<0.01) greater for patients treated with rivaroxaban compared to apixaban, and 1.2-fold (P=0.16) compared to those who received dabigatran.
• For the Cerner Health Facts Hospital cohort: Were 1.6-fold (P=0.04) greater for patients treated with rivaroxaban compared to apixaban, and 1.3-fold (P=0.30) compared to those who received dabigatran.

All-cause hospital readmission odds after adjustment for key patient characteristics (including above characteristics that were different between groups, during hospitalization):

• For the Premier Hospital cohort: Were 1.2-fold (P<0.001) greater for patients treated with rivaroxaban versus those treated with apixaban.

Conclusion

Using two separate large scale databases, patients with nonvalvular atrial fibrillation using different direct oral anticoagulants had different patient characteristics, including baseline stroke and bleeding risk. After adjustment for key patient characteristics, bleeding-related readmission risk was greater for rivaroxaban- versus apixaban-treated patients.

Find this article online at Curr Med Res Opin

References

1. Amin A, Jhaveri M, Lin J. Hospital readmissions in US atrial fibrillation patients: occurrence and costs. Am J Ther 2013;20:143-50
2. Johnson BH, Smoyer-Tomic KE, Siu K, et al. Readmission among hospitalized patients with nonvalvular atrial fibrillation. Am J Health Syst Pharm 2013;70:414-22
3. Deitelzweig SB, Pinsky B, Buysman E, et al. Bleeding as an outcome among patients with nonvalvular atrial fibrillation in a large managed care population. Clin Ther 2013;35:1536-45
4. Connolly SJ, Ezekowitz MD, Yusuf S, et al. Dabigatran versus warfarin in patients with atrial fibrillation. New Engl J Med 2009;361:1139-51
5. Patel MR, Mahaffey KW, Garg J, et al. Rivaroxaban versus warfarin in nonvalvular atrial fibrillation. New Engl J Med 2011;365:883-91
6. Granger CB, Alexander JH, McMurray JJV, et al. Apixaban versus warfarin in patients with atrial fibrillation. New Engl J Med 2011;365:981-2